Tex. Code Crim. Proc. art. 63.018

A physician who performs a postmortem examination on the body of an unidentified person shall complete and file a death certificate in accordance with Chapter 193, Health and Safety Code. The physician shall note on the certificate the name of the law enforcement agency that submitted the body for examination and shall send a copy of the certificate to the clearinghouse not later than the 10th working day after the date the physician files the certificate.